In regards to the issue of perf() not functioning on your pls objects, I’ve raised an error on the Github and implemented a fix for it. If you are wanting to use this build to work around the bug you reported, simply install the devtools library and run the following commands:
library(devtools)
install_github("mixOmicsTeam/mixOmics", ref = github_pull("197"))
If you are wanting to revert back to the standard release, navigate to your library folder within the R install directory, delete the mixOmics folder and then run the following line within RStudio:
BiocManager::install("mixOmics")
Let me know if this fixes your issue!
Cheers,
Max.